The present disclosure relates generally to computer systems, and, more particularly, to a system and method for managing the boot order of a computer system.
Computer systems, especially server systems, can be configured to boot from one of several available devices in the computer system. Modem computer systems permit a user to specify the boot device of the computer system. For example, the user of a computer system may instruct the computer system to boot from a specific hard drive, magnetic disk, CD-ROM or some other bootable device.
In the case of a computer system having one or more PCI buses, the computer system may boot from any one of the devices coupled to any of the PCI buses of the computer system. In computer systems having multiple PCI buses, the PCI buses are numbered. The first PCI bus is numbered 0 and the remaining PCI buses are numbered sequentially from 0. For each PCI bus, each device coupled to the PCI bus is uniquely numbered. Thus, each device that is coupled to a PCI bus may be identified by its PCI bus number and device number. As an example, the first device on the first PCI bus can be identified as device 0 on PCI bus 0. The second device on the first PCI bus can be identified as device 1 on PCI bus 0, and so on.
In prior computer systems, the boot order of the computer systems was determined by the computer system""s scan order. The computer system scanned the PCI devices of the computer system, starting with the PCI bus and device having the lowest number. Thus, the computer system would first attempt to boot from device 0 on PCI bus 0. If the computer system determined that it could not boot from device 0 on PCI bus 0, the computer system would continue its scan for a bootable device at device 1 of PCI bus 0. Alternatively, the direction of the boot scan could be reversed so that the boot scan would begin at the highest numbered PCI bus and device. If the user wished to boot from a particular device, the user had to physically install the device in the appropriate device slot so that the device would be the first bootable device encountered during the boot scan. This method of specifying the boot device was disadvantageous in that it required the physical manipulation of the bootable devices as a means of specifying the boot order.
More recent methods of specifying the boot order in a computer system having involved methods in which the user was permitted to manipulate the boot order by entering a BIOS system setup routine during start-up of the computer system. At startup of the computer system, a boot order routine in the ROM BIOS of the computer system typically presents for the user a list of bootable devices. The user could then choose among the list of bootable devices identified in the table to specify the boot order of the computer system. This method permitted the user to specify the boot order regardless of the location of the device in the computer system. This method, however, leads to a trial and error approach of selecting a bootable device for booting when multiple identical bootable devices are present in the computer system.
In accordance with the present disclosure, disclosed system and method for booting a computer system and determining the boot order of a computer system provides significant advantages over current computer system boot management techniques.
The boot order system and method of the present disclosure involves the display in a setup routine of the boot order of the computer system. The bootable devices of the computer system are identified by their name and by their location in the computer system. Because each bootable device is identified by both its name and its location in the computer system, each bootable device is uniquely identified, even in the case where there are multiple identical bootable devices in the computer system. In those systems in which the bootable devices are PCI devices, the PCI devices are identified in the boot order listing by the name of the PCI device, the PCI bus number, and the PCI slot number of the bootable device. The boot order list may also contain an identification of whether the PCI device is an embedded device and the operating speed and maximum speed of the PCI device.
A technical advantage of the boot order system and method is a boot order technique in which the computer user can positively identify bootable devices in those instances in which the computer system includes multiples of the same bootable device. Because each bootable device is positively identified, the computer user can change the boot order of the computer system without resorting to a trial and error approach for identifying the content of the bootable devices of the computer system.
Another technical advantage of the boot order system and method is that the boot order display will identify embedded PCI devices. Identifying embedded devices assists the computer user in identifying those devices that may be detached from the computer system and later reinstalled or replaced. Another technical advantage of the disclosed boot order system and method is the display of the actual operating speed of the bootable PCI devices, as well as the rated speed of the PCI devices, and the maximum operating speed of the PCI buses of the computer. Identifying the operating speed of the bootable devices allows the user to determine if a slower device has been installed or is slated to be installed on a faster bus, thereby causing a potential degradation in the performance of the computer system.
Other technical advantages will be apparent to those of ordinary skill in the art in view of the following specification, claims, and drawings.